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991.
Sheng-Wei Chang Jack Wellmerling Xiaoli Zhang Rachael E. Rayner Wissam Osman Sara Mertz Amal O. Amer Mark E. Peeples Prosper N. Boyaka Estelle Cormet-Boyaka 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(9):1988-1994
Background
Marijuana consumption is on the rise in the US but the health benefits of cannabis smoking are controversial and the impact of cannabis components on lung homeostasis is not well-understood. Lung function requires a fine regulation of the ion channel CFTR, which is responsible for fluid homeostasis and mucocilliary clearance. The goal of this study was to assess the effect that exposure to Δ9-tetrahydrocannabinol (THC), the psychoactive substance present in marijuana, has on CFTR expression and function.Methods
Cultures of human bronchial epithelial cell line 16HBE14o- and primary human airway epithelial cells were exposed to THC. The expression of CFTR protein was determined by immunoblotting and CFTR function was measured using Ussing chambers. We also used specific pharmacological inhibitors of EGFR and ERK to determine the role of this pathway in THC-induced regulation of CFTR.Results
THC decreased CFTR protein expression in primary human bronchial epithelial cells. This decrease was associated with reduced CFTR-mediated short-circuit currents. THC also induced activation of the ERK MAPK pathway via activation of EGFR. Inhibition of EGFR or MEK/ERK prevented THC-induced down regulation of CFTR protein expression.Conclusions and general significance
THC negatively regulates CFTR and this is mediated through the EGFR/ERK axis. This study provides the first evidence that THC present in marijuana reduces the expression and function of CFTR in airway epithelial cells. 相似文献992.
993.
994.
Liu Miao Li Siqi Xie Yongzhen Jia Shiru Hou Ying Zou Yang Zhong Cheng 《Applied microbiology and biotechnology》2018,102(3):1155-1165
Applied Microbiology and Biotechnology - Oxygen plays a key role during bacterial cellulose (BC) biosynthesis by Gluconacetobacter xylinus. In this study, the Vitreoscilla hemoglobin (VHb)-encoding... 相似文献
995.
996.
Shiyun Wang Rong Zhang Xuhong Hou Fusong Jiang Jie Wang Zhen He Feng Jiang Cheng Hu Weiping Jia 《中国科学:生命科学英文版》2018,61(11):1382-1388
We aim to investigate the relationship between serum somatostatin(SST) levels and glucose-lipid metabolism at various stages of glucose tolerance in the Jino ethnic minority(n=111) and Han population(n=113) of Yunnan Province, southwest China.Anthropometric parameters and biochemical traits were measured. Serum SST and plasma glucagon levels were tested. Participants were divided into three subgroups: isolated fasting hyperglycemia(IFH), isolated post challenge hyperglycemia(IPH)and normal glucose tolerance(NGT). SST levels were found lower while glucagon levels were significantly higher in the Jino ethnic with IPH(P=0.0026 and P=0.0069, respectively). Fasting glucose and high density lipoprotein-cholesterol(HDL-C)levels were higher(P=0.0055 and P=0.0021, respectively) and fasting insulin levels and homeostasis model assessments β-cell function were lower(P=0.0479 and P=0.0007, respectively) in the Jino population. After adjusting for confounding factors, the serum SST level was associated with glucagon(P0.0001) in both populations. The SST level was correlated with fasting Cpeptide(P=0.0267) in Jino and HDL-C levels in Han(P=0.0079). Our findings suggest that serum SST levels and plasma glucagon levels may vary in subjects with IPH between two ethnics. 相似文献
997.
Increasing evidence has shown that the energy use of ant colonies increases sublinearly with colony size so that large colonies consume less per capita energy than small colonies. It has been postulated that social environment (e.g., in the presence of queen and brood) is critical for the sublinear group energetics, and a few studies of ant workers isolated from queens and brood observed linear relationships between group energetics and size. In this paper, we hypothesize that the sublinear energetics arise from the heterogeneity of activity in ant groups, that is, large groups have relatively more inactive members than small groups. We further hypothesize that the energy use of ant worker groups that are allowed to move freely increases more slowly than the group size even if they are isolated from queen and brood. Previous studies only provided indirect evidence for these hypotheses due to technical difficulties. In this study, we applied the automated behavioral monitoring and respirometry simultaneously on isolated worker groups for long time periods, and analyzed the image with the state‐of‐the‐art algorithms. Our results show that when activity was not confined, large groups had lower per capita energy use, a lower percentage of active members, and lower average walking speed than small groups; while locomotion was confined, however, the per capita energy use was a constant regardless of the group size. The quantitative analysis shows a direct link between variation in group energy use and the activity level of ant workers when isolated from queen and brood. 相似文献
998.
Reducing Mg Anode Overpotential via Ion Conductive Surface Layer Formation by Iodine Additive
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Xiaogang Li Tao Gao Fudong Han Zhaohui Ma Xiulin Fan Singyuk Hou Nico Eidson Weishan Li Chunsheng Wang 《Liver Transplantation》2018,8(7)
Electrolytes that are able to reversibly deposit/strip Mg are crucial for rechargeable Mg batteries. The most studied complex electrolytes based on Lewis acid‐base chemistry are expensive, difficult to be synthesized, and show limited anodic stability. Conventional electrolytes using simple salts such as Mg(TFSI)2 can be readily synthesized, but Mg deposition/stripping in these simple salt electrolytes is accompanied by a large overpotential due to the formation of a surface layer on the Mg metal with a low Mg ion conductivity. Here the overpotential for Mg deposition/stripping in a simple salt, Mg(TFSI)2‐1,2‐dimethoxyethane (DME), electrolyte is significantly reduced by adding a small concentration of iodine (≤50 × 10?3m ) as an additive. Mechanism studies demonstrate that an Mg ion conductive solid MgI2 layer is formed on the surface of the Mg metal and acts as a solid electrolyte interface. With the Mg(TFSI)2‐DME‐I2 electrolyte, a very small voltage hysteresis is achieved in an Mg‐S full cell. 相似文献
999.
Effects of Growing Location on the Contents of Main Active Components and Antioxidant Activity of Dasiphora fruticosa (L.) Rydb. by Chemometric Methods
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Wei Liu Dongmei Wang Xiaogai Hou Yueqin Yang Xian Xue Qishi Jia Lixia Zhang Wei Zhao Dongxue Yin 《化学与生物多样性》2018,15(7)
Traditional Chinese Medicine (TCM) is a very important raw material source for natural medicines in China. The content and activity of active component are main indexes that evaluate the quality of TCM, however, they may vary with environmental factors. In this study, the effects of environmental factors on the active component contents and antioxidant activity of Dasiphora fruticosa collected from the five main growing areas of China were investigated. The contents of tannin, total flavonoids and rutin were determined to be 7.65 – 10.69%, 2.30 – 5.39% and 0.18 – 0.81%, respectively. Antioxidant activity was determined by DPPH assay, with the DPPH IC50 values ranged from 8.791 to 32.534 μg mL?1. In order to further explore the cause of these significant geographical variations, the chemometric methods including correlation analysis, principal component analysis, gray correlation analysis and path analysis were applied. The results showed that environmental factors had significant effect on the contents of active components and antioxidant activity. Rapidly available phosphorus (RAP) and rapidly available nitrogen (RAN) were common dominant factors, and a significant positive action existed between RAP and active components and antioxidant activity (P < 0.05). Contributed by their high active components and strong antioxidant activity, Bange in Tibet and Geermu in Qinghai Province were selected as a favorable growing location, respectively. 相似文献
1000.
Ying‐Ying Wang Bao‐Hua Hou Jin‐Zhi Guo Qiu‐Li Ning Wei‐Lin Pang Jiawei Wang Chang‐Li Lü Xing‐Long Wu 《Liver Transplantation》2018,8(18)
Presently, commercialization of sodium‐ion batteries (SIBs) is still hindered by the relatively poor energy‐storage performance. In addition, low‐temperature (low‐T) Na storage is another principal concern for the wide application of SIBs. Unfortunately, the Na‐transfer kinetics is extremely sluggish at low‐T, as a result, there are few reports on low‐T SIBs. Here, an advanced low‐T sodium‐ion full battery (SIFB) assembled by an anode of 3D Se/graphene composite and a high‐voltage cathode (Na3V2(PO4)2O2F) is developed, exhibiting ultralong lifespan (over even 15 000 cycles, the capacity retention is still up to 86.3% at 1 A g?1), outstanding low‐T energy storage performance (e.g., all values of capacity retention are >75% after 1000 cycles at temperatures from 25 to ?25 °C at 0.4 A g?1), and high‐energy/power properties. Such ultralong lifespan signifies that the developed sodium‐ion full battery can be used for longer than 60 years, if batteries charge/discharge once a day and 80% capacity retention is the standard of battery life. As a result, the present study not only promotes the practicability and commercialization of SIBs but also points out the new developing directions of next‐generation energy storage for wider range applications. 相似文献